We move on to that flash flooding emergency in phoenix. Heavy rain in that area, just minutes sweeping vehicles away and sending emergency crews to rescue people in their cars and homes and ginger zee is here with the story. And, boy, these pictures. So many and that's the thing. It wasn't just the numbers as far as the rainfall. Those are impressive alone but look at the number next to them. How quickly they fell, in 30 minutes almost two inches in scottsdale. So many having the same fate. The headline, too much, too fast. Nearly an inch of rain in just 30 minutes. Parts of phoenix, arizona, saw rivers of mud raging waters to four feet deep. At least eight people rescued after flash flooding inundated the region. Two teenage boys airlifted to safety after swift waters crippled their suv. They captured the dramatic rescue on their cell phone. It felt like probably five minutes but it was only 30 seconds. Got one view out here. Reporter: A young man and woman trapped in their pickup truck desperate for help. The driver of this sports car made it only two blocks before the debris filled current overtook him. All of a sudden his corvette comes bobbing down the water. Reporter: A 70-year-old woman was in her car when it was swept away by powerful waters moving through this neighborhood. And then there's this driver deciding to go for it but then a smart change of heart. The muddy waters rushed through yards and homes, many watching it all unfold right in their own backyard. To see a wall of water coming towards you, there's nothing you can do. Reporter: In tucson a similar story, three children rescued after getting caught up in a violent riverbed. They were just out playing and all of a sudden they realized they're surrounded by water.

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